The present invention relates to a microwave oven having a radiation detecting device.
In general, conventional microwave ovens employ a temperature detection system wherein a temperature sensor probe is inserted into food so as to directly measure the temperature within food, thereby controlling the temperature of the oven.
However, with the temperature sensor probe it is difficult to measure the temperature of food and vegetable small in size. Furthermore when a plurality of foods are placed in the oven, it is impossible to control the over-all temperature. The sensitivity of the temperature sensor probe is not satisfactoty. Moreover, utility of such a probe is low because it is cumbersome to insert the probe into food.
As disclosed in U.S. Pat. No. 2,595,748, there has been devised and demonstrated an oven temperature control system wherein the temperature of food is measured in terms of a quantum of radiation emitted therefrom. However, this system has a problem that the detection range of a radiation detector is limited so that the temperature control is affected by the shape of food.
In order to overcome this problem, there has been devised a system, as disclosed in Japanese Utility Model Laid-Open No. 51-126441, wherein a radiation or temperature sensor is scanned. However, since the temperature sensor is scanned, the accuracy in detection is not satisfactory, noise is generated and lifetime is short. When this system is applied to an oven having a turntable, it is very difficult to attain synchronization between the rotation of the turntable and the swinging movement of the temperature sensor so that the reduction to practice is almost impossible.